Attenuation of TCR-induced transcription by Bach2 controls regulatory T cell differentiation and homeostasis

Nat Commun. 2020 Jan 14;11(1):252. doi: 10.1038/s41467-019-14112-2.

Abstract

Differentiation and homeostasis of Foxp3+ regulatory T (Treg) cells are strictly controlled by T-cell receptor (TCR) signals; however, molecular mechanisms that govern these processes are incompletely understood. Here we show that Bach2 is an important regulator of Treg cell differentiation and homeostasis downstream of TCR signaling. Bach2 prevents premature differentiation of fully suppressive effector Treg (eTreg) cells, limits IL-10 production and is required for the development of peripherally induced Treg (pTreg) cells in the gastrointestinal tract. Bach2 attenuates TCR signaling-induced IRF4-dependent Treg cell differentiation. Deletion of IRF4 promotes inducible Treg cell differentiation and rescues pTreg cell differentiation in the absence of Bach2. In turn, loss of Bach2 normalizes eTreg cell differentiation of IRF4-deficient Treg cells. Mechanistically, Bach2 counteracts the DNA-binding activity of IRF4 and limits chromatin accessibility, thereby attenuating IRF4-dependent transcription. Thus, Bach2 balances TCR signaling induced transcriptional activity of IRF4 to maintain homeostasis of thymically-derived and peripherally-derived Treg cells.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Basic-Leucine Zipper Transcription Factors / deficiency
  • Basic-Leucine Zipper Transcription Factors / metabolism*
  • Cell Differentiation / immunology
  • Chromatin / metabolism
  • Colitis / immunology
  • Disease Models, Animal
  • Epigenesis, Genetic / immunology
  • Forkhead Transcription Factors / metabolism
  • Gastrointestinal Tract / immunology
  • Gene Expression Regulation / immunology
  • Homeostasis / immunology
  • Interferon Regulatory Factors / deficiency
  • Interferon Regulatory Factors / metabolism
  • Interleukin-10 / biosynthesis
  • Lymphocyte Activation
  • Mice
  • Mice, Inbred C57BL
  • Mice, Mutant Strains
  • Receptors, Antigen, T-Cell / metabolism*
  • Signal Transduction / immunology
  • T-Lymphocyte Subsets / immunology*
  • T-Lymphocyte Subsets / metabolism
  • T-Lymphocytes, Regulatory / immunology*
  • T-Lymphocytes, Regulatory / metabolism

Substances

  • Bach2 protein, mouse
  • Basic-Leucine Zipper Transcription Factors
  • Chromatin
  • Forkhead Transcription Factors
  • Foxp3 protein, mouse
  • IL10 protein, mouse
  • Interferon Regulatory Factors
  • Receptors, Antigen, T-Cell
  • interferon regulatory factor-4
  • Interleukin-10